Perhaps someone will set up a remote^1 web proxy that adds the suggested "Permissions-Policy: interest-cohort=()" HTTP header to disable FLoC. Browser extensions are great but there is nothing to stop Google from removing access to them through the Play Store at any time.
1. Another alternative is to run the proxy locally. I run a web proxy bound to the loopback.
The browser I use does not process Javascript or CSS. I therefore have to do nothing. :)
However, I would guess switching browsers is extremely unlikely for a great number of users. Google must know that. That is why they can do something like FLoC. They must know that not many users are going to switch browsers.
I was not suggesting it would be users who set up the proxy. On the contrary I was suggesting we might see someone set up a proxy to help users who are unable/unwilling to help themselves. There are so many simple things I do for myself that I see being set up as "SaaS"-type projects/businesses and then posted/discussed on HN.
1. Another alternative is to run the proxy locally. I run a web proxy bound to the loopback.